Jean Grey was one of the five original X-Men. An omega-level mutant telekinetic and telepath, Jean has gained near limitless powers as a recurrent host of the Phoenix Force. She is known for her many returns from death and as the deceased wife of Cyclops.

No, as it'd make here nearly in her Sixties. Think about it, we assume at the very least, the beast was 18 in this movie. This was supposed to be in 1963, so hank was 61 in the 2006 movie...If they do it, they're going to have to come up with a damn good excuse for it. This might be way too complicated, but if they really wanted to add her, I think they should open with a young Jean Grey in a coma as a result of her telepathic link with Annie, when Annie almost died. We see young Jean manifest an astral projection that appears as an older her (famke) that has amnesia. This older version of her finds the X-men and calls herself Madelyn Pryor and she likes the code name Phoenix. This could explain the origin of her multiple personalities. The x-men are trying to save little Jean in the coma from being attacked by sentinels, blah, blah, blah. The end of the movie starts off where the third movie began. This way, they can use astral projection or future Charles as an explanation for why Patrick Stewart can walk in all of the other movies. They have the opportunity to tie everything back together in this movie and explain some of the inconsistencies.

Way I see it is she should not be in it but I see Marvel having the real Jean (not the 60's version) come back sometime this year. I mean the X men has not had this much attention on them in a long while and with it being its 50th year something big has to happen right?.